sch20,

carbon steel equal cross tee pipe
石油,轻重工业,消防,电力,航天,造船等基础工程标准gb/t12459-2005
弯头90eldn250sch2020g抗hic
按照压力等级区分:3000lb,6000lb,9000lb或sch80,sch160,xxs.
sfenry forged stainless steel a403 wp316l joint